Portuguese farmers are turning their backs on Monsanto’s genetically modified MON810, which is the only GM crop commercially grown in the European Union, according to the Portuguese government.

Official government data shows that Portuguese farmers have reduced the number of hectares under GM maize cultivation for the second year in a row. Portugal is one of only five countries in the European Union that commercially cultivates GM maize.

The Portuguese GM Free Coalition announced Tuesday that farmers in Portugal have grown a total of 7069 hectares of Monsanto’s Bt maize in 2016, this is around 1500 hectares less than in 2014.

In July Economia Digital reported that Spanish farmers are also reducing the number of hectares under GM maize production fast.

GM maize plants contain Bt, an insecticide that kills the worms that eat them. Farmers in Spain and Portugal are convinced that GM maize cultivation eventually hurts yields. Cooperative members from Huesca in Spain claim to have conducted field studies that show lower productivity in the medium term.

The Coordinator of Farmers and Livestock Farmers’ Associations (COAG) and Friends of the Earth have also applied to the autonomous Spanish communities to ban GM maize as long as its wild relative, teosinte, is not eradicated.

Environmentalists fear that teosinte is spreading uncontrollably and that it has already been contaminated by GM maize. To combat this problem, they are asking that Monsanto’s GM maize is not grown for several harvests.